Hand operated shirring machine

ABSTRACT

A hand-operated machine for shirring casing onto a stuffing tube ( 1 ) includes a body through which the stuffing tube ( 1 ) covered in casing may pass. The shirring machine has casing engaging means ( 4 ) that engages the casing as the machine is pushed along the stuffing tube ( 1 ) from the discharge end ( 12 ) so that the casing is drawn onto the stuffing tube. The casing engaging means ( 4 ) also disengages the casing when it is pulled in the opposite direction. The shirring machine also includes grasping means ( 11 ) to manually move it back and forth along the stuffing tube ( 1 ).

FIELD OF THE INVENTION

This invention relates to a hand operated shirring machine and inparticular to a hand operated machine used to load casing material onthe stuffing tube of a food packaging machine.

BACKGROUND OF THE INVENTION

Food packaging machines that are used to produce continuous ordiscontinuous food products such as salamis or whole muscle productencased in netting force the food product through a stuffing tube sothat it is extruded or forced into packaging that is drawn off thestuffing tube. In the case of salami, moistened casing material is fedonto the outer surface of the stuffing tube. This is known as shirringthe casing onto the stuffing tube. The end of the casing is clipped andthen the food product is forced through the stuffing tube so that thecase is pulled from the stuffing tube as it is filled by the foodproduct.

It is similar in the case of whole muscled product which is encased inelastic netting. The elastic netting is shirred onto the stuffing tubeand drawn off as the product is forced out of the end of the stuffingtube.

At the beginning of each manufacturing process it is necessary to shirrthe required amount of casing material, or as much casing material as ispossible, onto the stuffing tube. This is normally carried out by handwhere the end of the elongate casing material is slid over the end ofthe stuffing tube with the casing material bunched or shirred onto thestuffing tube. This is obviously a time consuming process and reducesthe packaging efficiency of the machine. Alternatively, in someinstances it is possible to have removable stuffing tubes which can havepackaging material shirred onto the stuffing tube prior to it beingplaced on the packaging machine. This enables one stuffing tube to beshirred while another is being used on the packaging machine. However,one disadvantage is the increased capital cost of the equipment and alsothe time required to change over the stuffing tube. In addition, in someprocesses or with some machines, it is not possible to change thestuffing tube.

Accordingly, it is an object of this invention to provide a convenientmeans of loading casing material onto the stuffing tube and for thatprocess to be hand operated.

SUMMARY OF THE INVENTION

In its broadest form, the invention is a hand operated shirring machineincluding; a body through which a stuffing tube covered in casing maypass, a casing engaging means that engages said casing as the shirringmachine is pushed along said stuffing tube from its discharge end sothat said casing is drawn onto said stuffing tube and that disengagesfrom said casing when it is pulled in the opposite direction, andgrasping means for grasping said shirring machine to manually move itback and forth along said stuffing tube.

This machine enables casing material to be drawn onto the stuffing tubeto its maximum extent and then to release its engagement with the casingso that the machine can be drawn back along the casing over the stuffingtube so that another length of casing can then be engaged and pushedonto the stuffing tube. In this manner, the casing is bunched up in aconcertina fashion on the stuffing tube by the shirring machine. Thisprocess continues until the stuffing tube is fully covered in bunchedcasing. The casing can then be cut and the shirring machine removed fromthe stuffing tube so that the filling process can begin.

The shirring machine may be of a generally tubular shape and may includea hinge and lock mechanism allowing easy placement of the tube about thestuffing tube. The casing engaging means may comprise any form ofmechanism which is able to grip the casing when the shirring machine ismoved in one direction but release it when it is moved in the oppositedirection. It may comprise a plurality of annular segments that arespringloaded and slide longitudinally with respect to the tubular bodywithin a tapered section. The tapered section forces the segmentstowards the stuffing tube so that they grip the casing when it is movedin one direction. The springs release and open the segments when it ismoved in the opposite direction.

If the casing comprises an open net, then a plurality of spring-loadedfingers may extend from the end of the tubular body. The fingers may beconnected to a continuous circumferential spring which draws the fingersinwardly. Forward movement of the fingers causes them to engage and pushthe netting forward over the stuffing tube. Rearward movement causes thefingers to move outwardly against the spring force so that the fingersrun over the surface of the casing without it being drawn from thestuffing tube. Movement in the opposite direction causes the fingers toengage the casing and again force it onto the stuffing tube.

Preferably, the means for grasping the shir g machine comprise a pair ofhandles located either side of the tubular body. However, it would bepossible to use a single handle together with an abutment surface toenable operation by two hands. In some instances, the machine may beoperated by simply grasping the external surface of the tubular body.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to fully understand the invention, a preferred embodiment willnow be described with reference to the following drawings.

FIG. 1 is a cross-sectional view of a preferred embodiment of thepresent invention.

FIG. 2 is a perspective view of the invention illustrated in FIG. 1depicting the shirring of netted casing onto a stuffing tube.

FIG. 3 is a top perspective view of the invention illustrated in FIG. 1.

DESCRIPTION OF PREFERRED EMBODIMENT

Referring to FIG. 1, the shirring machine is shown located over astuffing tube 1 having a discharge end 12. The tubular body comprises afirst tube 5 that locates over the outer surface of the second tube 6.The second tube 6 locates over the stuffing tube 1. A plurality ofmounting brackets 3 are attached to and spaced around the outer surfaceof the first tube 5. Fingers 4 are pivotally attached to the mountingbrackets 3 and extend forward of the first tube 5.

A circumferential coil spring 10 locates through each of the fingers 4forward of the pivot point of the fingers 4. The coil spring 10 has theeffect of drawing the fingers 4 inwardly towards the stuffing tube 1.The first tube 5 slides with respect to the second tube 6. Disengagingmeans comprising a ring 2 having a tapered exterior section upon whichfingers 4 rest is located on the forward end of the second tube 6 andforces the fingers 4 apart as the first tube 5 slides rearwardly withrespect to the second tube 6. This enables the fingers 4 to be expandedoutwardly so that they can be held clear and disengage from the casingas the machine is placed onto the stuffing tube.

Referring to FIG. 2, fingers 4 are shown engaging the circumferentialstrands of the netted casing so that as the machine is pushed forward,the netted casing is drawn onto the stuffing tube 1. At the same time,the casing is being bunched up along the length of the stuffing tube 1.

In operation, the first tube 5 is pulled rearwardly with respect to thesecond tube 6 so that the ring 2 expands the fingers 4 as is shown inFIG. 3. Casing material, in this instance comprising netted casing isdrawn through the second tube 6 and pulled over the end of the stuffingtube 1. A tapered mandrel may be temporarily placed at the end of thestuffing tube 1 so that the netted casing can be expanded easily to pullover the end of the stuffing tube 1. The mandrel can remain in place asthe netted casing is being loaded.

The machine is then brought onto the end of the stuffing tube 1. Thering 2 holds the fingers 4 open so that the fingers 4 do not at thisstage engage the netted casing. The first tube 5 is then pushed forwardin relation to the second tube 6 so that the ring 2 is brought into itsrearward position in relation to the first tube 5 so that fingers 4 canbe pulled by the coil spring 10 into contact with the netted casing. Thehandles 11 are then used to manually push the shirring machine along thestuffing tube so that the ends of the fingers 4 engage the netted casingand pull it onto the stuffing tube 1. The netted casing in advance ofthe fingers 4 is bunched up while additional netted casing is beingpulled onto the stuffing tube 1.

Once the shirring machine reaches its limit of motion which is governedby the bunched section of netted casing, the machine is pulledrearwardly. The fingers 4 are able to expand and disengage from thenetted casing under the action of the coil spring 10 so that theshirring machine can slide over the netted casing. The machine is thenready to be pushed forwardly again. This process is repeated until thestuffing tube 1 is fully covered with netted casing. At the end of thisprocess, the machine is fully removed from the stuffing tube, the nettedcasing cut and the mandrel removed from the end of the stuffing tube.The netted casing can then be clipped so that the first portion of meatproduct can be pushed through the discharge end 12 of the stuffing tube.As it is, the casing is drawn from the end of the stuffing tube therebycovering the meat product in netted casing.

As will be seen from the above description, the invention provides avery convenient means of manually loading casing onto a stuffing tube.The invention dearly provides significant advantages in relation toother methods of shirring casing onto a stuffing tube.

It will be understood that the term “comprise” and any of itsderivatives (eg. comprises, comprising) as used in this specification isto be taken to be inclusive of features to which it refers, and is notmeant to exclude the presence of any additional features unlessotherwise stated or implied.

Although a preferred embodiment of the method and apparatus of thepresent invention has been illustrated in the accompanying drawings anddescribed in the foregoing detailed description, it will be understoodthat the invention is not limited to the embodiment disclosed, but iscapable of numerous rearrangements, modifications and substitutionswithout departing from the scope of the invention as set forth anddefined by the following claims.

1. A hand operated shirring machine including; a body through which astuffing tube covered in casing may pass, a casing engaging means thatengages said casing as the shirring machine is pushed along saidstuffing tube from its discharge end so that said casing is drawn ontosaid stuffing tube and that disengages from said casing when it ispulled in the opposite direction, and grasping means for grasping saidshirring machine to manually move it back and forth along said stuffingtube.
 2. A hand operated shirring machine as claimed in claim 1 whereinsaid casing engaging means includes a plurality of annular segmentsarranged about the circumference of said stuffing tube.
 3. A handoperated shirring machine as claimed in claim 1 wherein said casingengaging means includes a plurality of fingers pivotally attached tosaid body arranged about the circumference of said stuffing tube.
 4. Ahand operated shirring machine as claimed in claim 3 wherein saidfingers are connected to a continuous circumferential spring biased todraw said fingers towards said stuffing tube.
 5. A hand operatedshirring machine as claimed in claim 1 wherein said casing engagingmeans includes a spring mounted member located in a tapered section onsaid body wherein as said member slides longitudinally with respect tosaid body within said tapered section said member is forced to grip thecasing when said member is moved in one direction and release the casingwhen said member is moved in an opposite direction.
 6. A hand operatedshirring machine as claimed in claim 1 wherein said body is tubular. 7.A hand operated shirring machine as claimed in claim 1 wherein said bodyincludes a first tubular section having disengaging means, a secondtubular section having casing engaging means interfacing with saidtapered portion, wherein first and second tubular sections are slidablymovable a predetermined distance relative to each other so that saidcasing engaging means is forced to grip said casing when said first andsecond tubular sections are slid apart from each other and disengagingmeans acts upon said casing engagement means to release said casing whensaid first and second tubular sections are slid towards each other.
 8. Ahand operated shirring machine as claimed in claim 7 wherein said casingengaging means includes a plurality of annular segments arranged aboutthe circumference of said stuffing tube.
 9. A hand operated shirringmachine as claims in claim 7 said casing engaging means includes aplurality of fingers pivotally attached to said second tubular sectionarranged about the circumference of said stuffing tube.
 10. A handoperated shirring machine as claimed in claim 9 wherein said fingers areconnected to a continuous circumferential spring biased to draw saidfingers towards said stuffing tube.
 11. A hand operated shirring machineas claimed in claim 1 wherein said grasping means include a pair ofhandles.
 12. A method of loading casing onto a stuffing tube comprising:inserting a tapered mandrel into a discharge end of said stuffing tube;drawing an end of said casing over said mandrel and sliding said end ofsaid casing onto the discharge end of said stuffing tube; bringing thehand operated shirring machine as claimed in claim 1 onto the end ofsaid stuffing tube; and manually operating said hand operated shirringmachine to draw casing onto said stuffing tube forming a region ofbunched casing away from said discharge end of said stuffing tube.13-15. (canceled)